Front control arm flip

[Dusty]

I don't see your point on the "y" link, your shock are just longer witch let the axle drop out, I would call that a bad idea with no control over your axle and loss of stability. Some times it's not all about flex.

if you want to to climb extremely uneven surfaces that rise steeply in such a way as to allow for uneven plane (ie rockcrawling) then flex is paramount.

flex allows for all tires to be on the rock thus allowing maximum traction. traction allows one to place forces to the rock-both forces to propel one forward and to slow one down (brake)

any loss of "control" had from a flexy suspension (such as the tendancy to roll) is more that compensated with all the traction

my truck is much safer now in the rocks with more flex


the oe 80 series radius arms dont "droop" save for a few inches. to get flex from the front of an 80 you must force it into a position it does not want to take-similar to leaf springs. consequently when the front end is forced into flex it tends to unload violently seemingly randomly when bouldering-it is not subtle. 3 link the front of your 80 and watch how fast you can fly through extremely uneven terrain.

 

[Nay]

more flex is almost always better --the tire that unfortunatly falls in the hole in Nays example of the overly flexable jeep will be the same tire that stays on the rock and offers needed traction when a stiff 80 series lifts a tire.

This is true, as long as you haven't introduced other unfavorable dynamics. The Jeep SUV long arm conversions were known for solving the steep short arm/binding problem but introducing an unloading (and clearance) problem - a mid arm 3 link was a better solution, but isn't bolt on, so isn't sold. The risk is always trading one problem for another when you really go custom and overly biasing your dual purpose rig to a particular use (if in fact it is really still dual purpose).

You definitely have a sweet build and it is quite unconventional. Once you are out of the box in usage, might as well roll with it

 

[Dusty]

This is true, as long as you haven't introduced other unfavorable dynamics. The Jeep SUV long arm conversions were known for solving the steep short arm/binding problem but introducing an unloading (and clearance) problem - a mid arm 3 link was a better solution, but isn't bolt on, so isn't sold. The risk is always trading one problem for another when you really go custom and overly biasing your dual purpose rig to a particular use (if in fact it is really still dual purpose).

You definitely have a sweet build and it is quite unconventional. Once you are out of the box in usage, might as well roll with it

the 3 link front on my truck isn't terribly unstable but my current 80 is most certainly no longer the comfortable daily driver the pre-build 80 was. And i miss that. when she had 37's my 80 was the do it all the truck. the summer before my build i drove my entire fam for the last time on a road trip. we drove from california to arizona with 37's and then did one the hardest trails out there. That said I didn't have a tow vehicle then. now I simply leave the tires at 8psi all the time and trailer the rig everywhere. i can load and unload the rig faster than most can deflate their tires.

An 80 with a modified mid-joint radius arm would not be as nice as the 3 link but would be much more flexable and almost as stable as the current oe radius arm. whyhasn't someone gone this route? it wouldn't compromise the tierod.

Here is how you build a better radius arm for the 80 for less than 100 bucks and in a single day (a short day):
must start with a truck with 3" of limited uptravel (bump stops) to make room for the upper links
1. keep the frameside linkage bracket just as they are and keep the oe radius arm just like it is except chop off the front most rubber bushing from the oe radius arm
2. cut the front half of the oe axle side radius bracket off and discard. not needed anymore
3. fab and weld an upper link bracket for both the left and right side of the axle-a piece of 2" x 1/4 wall" square tube will work great. the pass side will need to be welded on top of the pumpkin like any other 3 link but doesn't need to be as high as a conventional 3 link because there will be a link on bothe sides. 6" seperation would be plenty.
4. use the bushing that was chopped off the front of the oe radius arm for the upper axle side of the new radius arm. now weld a piece of 1.5" pipe from that salvaged bushing to a 1" shank heim joint which will be located in a bracket welded midway on top the oe radius arm

done. now wasn't that easy?

only parts you need to buy:
3 feet of 2" x 1/4" square tube for use of all the link bracket (axle side and mid radius arm side)
2 7/8" shank heim joints (1.250" shank heims even better)
hardware for the new arms (you need only the 2 bolts for the heim joints all the rest of hardware is reused)

JP come over to my house with your truck. bring 2 heims. i have everything else

 

[Dusty]

instead of fabbing the extra upper arm for the new radius find an extra set of rear upper arms and use them

 

[cruiserdan]

You certainly "doctored" that truck up quite nicely.

I imagine that your patients fare at least that well.

If so I would like to be added to your client list.....


You left room for the golf clubs?

 

[jodo]

I also pondered the whole radius arm vs multi link (front). I ended up going with a radious arm thats been tested true. I figured that any system that I chose would have to be adjustable. I startered out with rubicon JK long arms. I wanted to keep them as paralell as possable to prevent axel streer.



Here you see the new arm is slightly longer then stock (good thing).



I moved the sterring up front using a RHD knuckle arm and chevy 1 Ton tie rod ends and DOM tube (very easy). This cleared the back of the axel for all kinds of possabilities.

 

[jodo]

This coupled with a pair of FOX "14 coilovers and Curry "TJ" towers (modified) ended up working quite nice. I'm currently chasing a few bugs out but so far would not change anything. Well, I some times wonder about good old leaf springs... rancho 44044's in front and 53" chevy's in rear... Wha, wha the F%$#! Ok, that was just a dream (previous rock crawler that I owned/built that worked perfect).





Jodo

 

[jodo]

I read what you guys had to say which all made good sense but... It's already been said.

Dusty, you inspired me for my build. I put my own twist on it to meet my specifications/expectations and so far I'm very happy. For the rear, I have made new super flexy arms (bent) but intend to do radious arms simular to Dusty's in the rear.

Jodo

 

[Dusty]

You certainly "doctored" that truck up quite nicely.

I imagine that your patients fare at least that well.

If so I would like to be added to your client list.....


You left room for the golf clubs?

I have a large crawler clientel. its the first thing i ask new patients..."so do you have a big truck?....
And I hate golf. just like the carts...and by the way i wrecked my golf cart this past weekend-i was racing full bore down a steep dirt path in the forest and couldn't stop. i had to bail out of the cart which hit a tree. ill fix it-soon i will have a 6x6 duece electric golf cart-pending

I read what you guys had to say which all made good sense but... It's already been said.


Dusty, you inspired me for my build. I put my own twist on it to meet my specifications/expectations and so far I'm very happy. For the rear, I have made new super flexy arms (bent) but intend to do radious arms simular to Dusty's in the rear.

Jodo

man where has this build been hiding? post up a build thread. i see you also used currie brackets for the axles. keep the pics comin. 37's?

i see you will need a new tranny supporting member

and the rear radius arm on my truck is working great. But likely not any better than stock. if you arnt lifting yours much you probably dont need to mess with the rear. I only did because I needed the D70 to run lower gears than were poss with the yota rear which is plenty stout (with an ARB)

 

[Nay]

An 80 with a modified mid-joint radius arm would not be as nice as the 3 link but would be much more flexable and almost as stable as the current oe radius arm. whyhasn't someone gone this route? it wouldn't compromise the tierod.

NWSickboy did a front y-link years ago, I am also surprised it never caught on.

I would agree that you would not sacrifice much if anything in stability with this conversion, and I like that Rubi arm base that was used in the build below.

Another major advantage: you just got adjustable caster if you use a threaded arm in the "upper" link.

I agree that 37's are the "do it all" build. This y-link really has me thinking, having run a long arm conversion on my old XJ...any reason to angle the upper mounts in like the Jeep setup? Simply retaining the stock arm as Dusty has outlined makes very good sense, do a heim on the mount to the stock arm and a rubber bushing on the axle end, right?

 

[Nay]

Well, I some times wonder about good old leaf springs... rancho 44044's in front and 53" chevy's in rear... Wha, wha the F%$#! Ok, that was just a dream (previous rock crawler that I owned/built that worked perfect).

Me too, but only for the rear, 3-link the front. Would work perfect and be totally stable on 6"-7" of lift.

 

[Tools R Us]

Nice work, have seen that method of moving the tie rod to the front on a SAS Taco, but he used the stock arms, flipped side to side, heated and bent.

Dan, can you get that right hand drive arm?

I'm pretty happy with the 3 bushing arms, but a three link would be a nice option. My concern would be high speed, even the "no sway bar" guys comment on how much mine leans on highway turns and it has sway bars.

 

[-Spike-]

now weld a piece of 1.5" pipe from that salvaged bushing to a 1" shank heim joint which will be located in a bracket welded midway on top the oe radius arm

Please forgive my welding ignorance. I thought there was an issue with welding to the stock arms...?

 

[nicholas]

Please forgive my welding ignorance. I thought there was an issue with welding to the stock arms...?

I was wondering about that too. I thought they were cast-iron which I have heard is less than ideal to weld.

 

[locrwln1]

Please forgive my welding ignorance. I thought there was an issue with welding to the stock arms...?

Actually they are very nice to weld to.

I lengthened my stock arms to compensate for the 4" lift, now the front axle is centered in the wheel opening and I don't hit the bumpstops inside the front springs.

Now before anyone worries about my "School bus full of nuns and orphans" killing modification, it's been holding up just fine for about a year with many, many miles (roughly 7k) of hard and fast dirt road, some rockcrawling and highway time.

Turn up the heat on the welder and you can watch a beautiful weld puddle appear before your eyes. I would venture with the proper prep and techniques, that the welding will hold up as well or better than the stock arm.

I added about 7/8" to the length. Cut them about 8" from the rear bushing and built a new section of "I" beam to weld in with 3/8" thick steel. Then I added some metal (about 6") to the sides for reinforcement over the extension, cleaned and painted them up. The final product could have been little prettier, but it is very strong.

Jack

 

[cruiserdan]

Dan, can you get that right hand drive arm?

Not without the VIN, production date and Japan Model Code off of a RHD vehicle that is currently in the United States.

 

[Tools R Us]

I was wondering about that too. I thought they were cast-iron which I have heard is less than ideal to weld.

They are cast steel, with enough heat they weld well. I know of one who made a wristed arm, by cutting the arm and welding a hinge joint and disconnect under the tie rod. Someone else on this form, cut angled and welded them back for caster correction.

 

[Nay]

instead of fabbing the extra upper arm for the new radius find an extra set of rear upper arms and use them

The heim (or johnny joint) is better - it makes caster adjustable.

 

[Dusty]

NWSickboy did a front y-link years ago, I am also surprised it never caught on....

Another major advantage: you just got adjustable caster if you use a threaded arm in the "upper" link....

....any reason to angle the upper mounts in like the Jeep setup? Simply retaining the stock arm as Dusty has outlined makes very good sense, do a heim on the mount to the stock arm and a rubber bushing on the axle end, right?

yea but sickboy did a rigid radius on only one side right?

the only reason jeep angle the "upper" link in is to clear the spring. same applies for our trucks. we need to angle in also just as was done in the above pic. and an adjustable link would totally eliminate the castor issue

Me too, but only for the rear, 3-link the front. Would work perfect and be totally stable on 6"-7" of lift.

yea but it would be cheaper and work better to reuse the rear coils

....I'm pretty happy with the 3 bushing arms, but a three link would be a nice option. My concern would be high speed, even the "no sway bar" guys comment on how much mine leans on highway turns and it has sway bars.

give plenty of seperation between the upper and lower links and move the pass side upper link inward so it sits on top the pumpkin and this wont be an issue. use all heims or rebuildable joints instead of rubber and the front end is absolutely solid. the potential onroad instability of a 3 link (single radius arm is even worse) is not due to geometry issues but due to the misalignment of rubber bushings-lateral and vertical misalignment is magnified due to less rubber bushings to share the loads. stay with non-misaligning joints and its not an issue

Please forgive my welding ignorance. I thought there was an issue with welding to the stock arms...?

as others have said. the steel from which the oe arms are made is high quality stuff. weld away

 

[Nay]

yea but sickboy did a rigid radius on only one side right?

I don't remember - seems it was y-radius on both sides. I seriously considered buying that rig 4 years ago, but I was convinced I wasn't going 37's and I didn't want a big lift

the only reason jeep angle the "upper" link in is to clear the spring. same applies for our trucks. we need to angle in also just as was done in the above pic. and an adjustable link would totally eliminate the castor issue

Makes sense...

yea but it would be cheaper and work better to reuse the rear coils

Not necessarily if you are upgrading the axle, too, and want to go taller. You just need spring pads and shock mounts for leafs, and you sell your HD LCA's, rear coils, adjustable panhard, and factory axle to partially offset the cost, using Chevy springs for the new build.

A flat leaf at 7" of lift is going to have good geometry compared to an angled link system and can be easily made to flex out a 12" travel shock. Get rid of the swaybar and all the other crap back there. Very simple way to run more lift with good stability/geometry in the rear suspension for a heavy rig. Although I'd want 39's with more lift, and then we get back into daily driveabilty, so it ain't gonna happen any time soon. You want to tune these things in my mind more than forklift upgrade them (to the point of reusing the stock arms for a y-link...extremely simple retention of stock parts to improve flex).

give plenty of seperation between the upper and lower links and move the pass side upper link inward so it sits on top the pumpkin and this wont be an issue. use all heims or rebuildable joints instead of rubber and the front end is absolutely solid. the potential onroad instability of a 3 link (single radius arm is even worse) is not due to geometry issues but due to the misalignment of rubber bushings-lateral and vertical misalignment is magnified due to less rubber bushings to share the loads. stay with non-misaligning joints and its not an issue

This is a good point - mount separation (8" is desired) and parallel alignment of upper and lower arms is a key to keeping stability. A 3 link with all rigid joints (no bind in the system requiring bushing deflection means get rid of the rubber) is an excellent way to firm up the front end. There is no functional reason for a 3 link to be unstable - a single upper link will easily control housing rotation, and the heavier duty the housing, the more you should have nothing to worry about (you aren't going to twist the housing under load) assuming you don't screw up your single upper arm link mount

Tools, it is interesting that your rig leans a lot by losing one forward mount. Is that really just road bushing restriction in the stock design or is it now a geometry issue?